1. Field of the Invention
This invention relates to structural framework systems and more particularly it concerns novel clamp elements, clamp assemblies, frame assemblies and frame assemblies which can be readily disassembled and reassembled in various configurations.
2. Description of the Prior Art
Clamped framework assemblies have proven to be especially desirable for many applications because of their high strength and ease of assembly and disassembly. Also, clamped framework assemblies can be reconfigured quite readily for various applications, including formation of shelves, supports, display racks, false ceilings, etc.
One particularly advantageous structural framework system is the Powerclamp.RTM. structural tube and fitting system sold by Uni Corp., 50 Manida Street Bronx, N.Y. and shown and described in Uni Corp catalog C-200. That system comprises a plurality of elongated framework members arranged in a three dimensional grid formation and clamped together at their intersections by special clamping assemblies. Each clamping assembly comprises a plurality of clamp elements. The clamp elements are formed with recesses whose inner surfaces extend part way around and conform to the outer surface configuration of the elongated members. Fastening means, such as bolts, extend between clamp elements on opposite sides of the elongated members and hold the clamp elements tightly to the elongated members.
In the construction of a three dimensional grid type framework assembly, clamping assemblies must be provided which will accommodate elongated structural members extending in three orthogonal directions from the clamping assembly. In the past, this has required at least three clamp elements in each assembly; and at least one of the clamp elements had to be formed with recesses extending in three different directions. Also, two sets of fastening means were required to operate in different clamping directions on the same clamping element. This contributed substantially to the cost and complexity of the clamping system.
Other clamped framework systems and clamping assemblies are shown and described in U.S. Pat. Nos. 998,904, 1,166,688, 1,261,213, 3,021,159, 4,283,152, 4,421,434, Des. 157,594, and Des. 275,075 as well as Austrian Pat. No. 229,642, French Patent No. 1,287,983 and Italian Patent No. 419,599.
U.S. Pat. No. 998,904 shows bifurcated clamp arrangements but not a three dimensional framework system. U.S. Pat. No. No. 1,166,688 shows a setscrew type clamping assembly with a single clamp element. U.S. Pat. No. 1,261,213 shows two element clamp arrangements but not a three dimensional clamp assembly. U.S. Pat. No. 3,021,159 shows clamping assemblies with split clamp elements which are flexible and squeezed around elongated members. U.S. Pat. No. 4,283,152 shows two element clamping assemblies but not a three dimensional framework system. U.S. Pat. No. 4,421,434 shows a multiple element clamping assembly for a three dimensional framework system but the clamping assembly requires at least three elements for a three dimensional intersection and at least one of these elements is subjected to clamping forces in two different directions. U.S. Pat. No. Des. 157,594 shows a two dimensional coupling arrangement but no clamping. U.S. Pat. No. Des. 275,075 shows a clamping assembly like that shown in U.S. Pat. No. 4,421,434. Austrian Patent No. 229,642 and French Patent No. 1,287,983 shows two element clamping arrangements for a three dimensional framework system but the clamping elements themselves only clamp in two dimensions and they are held together, in part, by the action of elongated members extending in a third dimension. Italian Patent No. 4,419,599 shows bifurcated clamping assemblies but not a three dimensional framework assembly.